1. Field of the Invention
The present invention relates to a method for manufacturing a liquid cartridge and a liquid cartridge. More particularly, the present invention relates to a method for manufacturing a liquid cartridge and a liquid cartridge, which has a supply valve in a liquid supplying part.
2. Description of the Related Art
The ink cartridge holds ink therein and supplies the ink held therein to a recording head of an inkjet type recording apparatus when mounted onto a carriage equipped with the recording head. In the ink cartridge, a supply valve and a seal member for being in contact with the supply valve are provided in an ink supply section into which an ink supply needle of the inkjet type recording apparatus is inserted. In a state where the ink cartridge is not mounted on the carriage, the supply valve seals the seal member so that the ink does not leak out from the ink cartridge. In addition, in a state where the ink cartridge is mounted on the carriage, since the ink supply needle of the inkjet type recording apparatus moves the supply valve, the supply valve opens the seal member, and thus the ink is supplied to the recording head. For example, as a supply valve of the ink cartridge, a ball valve has been used as disclosed in Japanese Patent Application Publication No. 5-229137. Further, the ink cartridge, the inkjet type recording apparatus and the recording head here are an example of the liquid cartridge, the liquid ejecting apparatus and the ejecting head.
However, in the ball-shaped supply valve, there is a possibility that the ink supply needle is not always in contact with the center part of the ball-shaped supply valve, so, in this case, the supply valve cannot move in a supply-needle-insertion direction of the ink supply needle because it turns around. For this reason, there is a possibility that the supply valve is not opened and the ink cannot be supplied even though the ink supply needle is in contact with the supply valve.
Further, when the ball-shaped supply valve is mounted on the ink cartridge, a coil spring is inserted into the ink supply section and then the ball-shaped supply valve is inserted into the ink supply section into which the coil spring has been inserted. Next, the supply valve is temporarily stopped by a fixture in a state where the ball-shaped supply valve urged by the coil spring is pushed inwardly, and then a seal member is fitted into an ink supplying opening. After that, the fixture is removed from the ink cartridge. Consequently, the supply valve closes the ink supplying opening by an urging force of the coil spring. The method for assembling the ink supply section above is difficult and also takes time to assemble because of using the fixture. Therefore, there is a problem that the production cost of the ink cartridge becomes increased.
In addition, when the fixture is inserted into the ink supply section in order to fill ink during a process of filling ink, it is impossible to attach a film or the like for preventing the seal member from being fallen off, so that there is a problem that the seal member is fallen off or tilted by the urging force from when the seal member is fitted to when the film for preventing falling off is attached.